Calculating Capacitor Charge and Potential Difference in Series

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When capacitor C1, charged with Q0, is connected to an uncharged capacitor C2, the charges redistribute according to the formulas Q1 = Q0C1/(C1 + C2) and Q2 = Q0C2/(C1 + C2). The potential difference across both capacitors can be calculated with V = Q0 / (C1 + C2). It is emphasized that in equilibrium, the total voltage around the loop is zero, and the charge lost by C1 equals the charge gained by C2. Understanding the relationship between charge, capacitance, and voltage is crucial for manipulating the formulas correctly.
Soaring Crane
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A capacitor C1 carries a charge Q0. Is is then connected directly to a second, uncharged, capacitor C2.

What charge will each carry now? Q1 = Q0C1/(C1 + C2); Q2 = Q0C2/(C1 + C2)


What will be the potential difference across each?
V = Q0 / (C1 + C2)

-------||-------||--------
|*****C1*****C2******|
|********************|
|********************|
|********************|
|_______________________|

I know that the formula Q = CV is used, but how do you manipulate it (other than V = Q/C) to get the answers in bold?

Thanks.
 
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The voltage around the loop will be 0 in equilibrium, and whatever charge the second capacitor gets, the first one must lose. Does that help at all?
 
Soaring Crane said:
I know that the formula Q = CV is used, but how do you manipulate it (other than V = Q/C) to get the answers in bold?
Since the capacitors are connected in parallel, they have the same voltage (V). So the charges on the capacitors are: Q_1 = C_1V and Q_2 = C_2V. The total charge remains the same, so Q_0 = Q_1 + Q_2. Solve for V.
 
I think I understand what you're saying, but I don't know how to apply it to the questions.
 
Oh, OK. Let me try it.
 
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